Abstract:
A plurality of liquid jet nozzles are positioned in spaced apart relation to each other about a portion of the exterior surface of a pipe to be cleaned. High pressure liquid is supplied to the nozzles to cause liquid jets to be emitted, with the liquid jets being directed toward the exterior surface of the pipe. Each nozzle can be rotated about an axis which is at least substantially normal to the exterior surface of the pipe, while the nozzles are being moved longitudinally relative to the pipe. The liquid jets from the nozzles simultaneously impinge on the exterior surface of the pipe along prescribed paths located in an annular region extending around the circumferential extent of the pipe. Each of the prescribed paths is in the form of continuous convolutions, and the prescribed paths together extend around the full circumferential extent of the pipe while the annular region travels longitudinally relative to the pipe, whereby cleaning of the exterior surface of the pipe can be affected by a single longitudinal pass of the annular region.
Abstract:
Apparatus for the hydrocleaning of the exterior surface of a pipeline or the like includes a frame adapted to surround a portion of a pipeline and defining a longitudinal passage through which, in use, the pipeline extends. A plurality of liquid jet nozzles are mounted to the frame in spaced apart relation so as to surround, in use, said pipeline in circumferentially spaced apart relationship to one another with each nozzle in spaced relation to the pipeline exterior surface. Means for supplying high pressure liquid to the nozzles to cause liquid jets to be emitted from the nozzles are provided. The nozzles and the frame are adapted to move relative to the pipeline surface when in operation such that (i) the liquid jets from the nozzles impinge on the pipeline surface along prescribed paths located in an annular region extending around substantially the full circumferential extent of the pipeline and (ii) the annular region travels longitudinally relative to the pipeline to effect cleaning of the pipeline exterior surface. In one form of the machine the frame "opens" up to permit installation on an "in situ" pipeline.